Subtropical High Anomalies over the Western Pacific and Its Relations to the Asian Monsoon and SST Anomaly

Using the data of 500 hPa geopotential height from 1951 to 1995, SST roughly in the same period andOLR data from 1974 to 1994, the relation between the anomalies of subtropical high (STH for short) andthe tropical circulations including the Asian monsoon as well as the convective activity are studied. In orderto study the physical process of the air-sea interaction related to STH anomaly, the correlation of STH withSST at various sea areas, lagged and simultaneous, has been calculated.Comparing the difference of OLR, wind fields, vertical circulations and SST anomalies in the strong andweak STH, we investigate the characteristics of global circulations and the SST distributions related to theanomelous STH at the western Pacific both in winter and summer Much attention has been paid to the study ofthe air-sea interaction and the relationship between the East Asian monsoon and the STH in the western Pacific.A special vertical circulation, related to the STH anomalies is found, which connects the monsoon current to thewest and the vertical flow influenced by the SST anomaly in the tropical eastern Pacific.